Polymeric Cutting Edge Structures And Method Of Manufacturing Polymeric Cutting Edge Structures

ABSTRACT

A functional polymeric cutting edge structure and methods for the manufacturing of cutting edge structures comprised of polymeric materials are provided. The cutting edge structures may be produced on a substrate having a blade body or blade support type. The polymeric material is produced by curing a precursor material by electromagnetic radiation wherein a wavelength of said radiation is about double a wavelength required to cure the precursor material. A razor blade for use in a razor cartridge or a blade box may be formed using the present invention.

FIELD OF THE INVENTION

This invention relates to shaving razors and methods of manufacturingcutting edge structures, and more particularly to manufacturing cuttingedge structures such as shaving razor blades from a polymeric material.

BACKGROUND OF THE INVENTION

Razor blades are typically formed of a suitable metallic sheet materialsuch as stainless steel, which is slit to a desired width andheat-treated to harden the metal. The hardening operation utilizes ahigh temperature furnace, where the metal may be exposed to temperaturesgreater than about 1000° C. for up to about 20 seconds, followed byquenching, whereby the metal is rapidly cooled to obtain certain desiredmaterial properties.

After hardening, a cutting edge is formed generally by grinding theblade. The steel razor blades are mechanically sharpened to yieldcutting edges that are sharp and strong to cut through hair over anextended period of time. The continuous grinding process generallylimits blade shapes to have straight edges with a substantiallytriangular or wedge shape profile (e.g., cross section). The cuttingedge wedge-shaped configuration typically has an ultimate tip with aradius less than about 1000 angstroms.

The advantage of this prior method is that it is a proven, economicalprocess for making blades in high volume at high speed. It would beparticularly desirable if such a process could utilize lower costmaterials for blade formation and also enable cutting edged profilesother than substantially triangular.

Blades with cutting edges made from a polymeric material are disclosedfor disposable cutlery or disposable surgical scalpels (e.g., U.S. Pat.No. 6,044,566, U.S. Pat. No. 5,782,852). Razor blades made frompolymeric material are disclosed in GB2310819A. The disadvantage of anyof the prior art polymer blades is that the process of making suchplastic blades is not cost-effective for mass production nor suitable tocreate a cutting edge with a tip radius of less than 1 μm as requiredfor cutting hair.

Generally, the prior art utilizes melt flow processing techniques. Themolten polymer of the prior art is injected into a cavity of a mold toolwhich is typically metal, but the polymer is generally too viscous(typically exceeding 100,000 centiPoise) to fully penetrate into thesub-micro-meter (e.g., less than 1 micrometer) dimensioned spacesrequired in a cavity to create razor blade edges. However, choosing alower viscosity material or increasing the injection pressure, which maybenefit penetration into sub-micro-meter dimensioned spaces, causes thepolymeric material to penetrate between the mating surfaces of the twohalves of the mould tool, known as “flashing,” and therefore therequired cutting edge tip radius cannot be achieved. A decrease ofviscosity of the polymeric material may also be obtained by heating thepolymeric raw material above the glass transition temperature, oftenexceeding 200° C. Furthermore, after filling the cavity, the fluidpolymeric material needs to be cooled to achieve a solid state, whichcauses shrinkage of the blade shape and rounding of the edge andtherefore the required cutting edge tip radius cannot be achieved.

Therefore, a need exists for better processes for cutting edgestructures made of polymer and more cost-effective methods of makingcutting edge structures for shaving razors having required tip radius,less variability in edge quality and sharpness to provide a comparableor improved shaving experience.

It is also desirable to find materials and processes that can formcutting edge structures having any shape, such as non-linear edgesand/or provide an integrated assembly.

Recently additive manufacturing techniques, such as stereo lithographyand 3-dimensional printing have become widely used to fabricatepolymeric structures. In both cases, a 3-dimensional object is build upfrom small volume elements, so-called voxels, of material that aresuccessively added to each other until the entire object is formed.However, the spatial resolution of these techniques is limited to thesize of an individual pixel of tens of micro-meters, which is greaterthan the ultimate tip radius of a cutting edge.

High resolution additive manufacturing, such as 2-photon polymerization(2PP) described for instance in Photonics Spectra Vol. 40 (2006), Issue10, Pages 72-80, is known and its potential to create sub-micron sizedobjects has been demonstrated for micro-mechanical actuators (e.g., U.S.Pat. No. 7,778,723B2), micro-fluidics devices, optical elements (e.g.,U.S. Pat. No. 8,530,118B2), photonic crystals (e.g., US2013/0315530A1)and bio-medical applications such as micro-needles (e.g., US PatentPublication No. 2009/099537A1, CN103011058A) and tissue engineeringscaffolds (e.g., US Patent Publication No. 2013/012612A1).

All of these structures make use of high resolution additivemanufacturing on very small object length scales (e.g., 1 mm or less).One disadvantage of this process is that a certain time is required tocreate each individual voxel and hence the overall size of the completeobject determines the time required for its fabrication. Therefore, aneed exists to fabricate larger objects, such as razor blades, usinghigh resolution additive manufacturing on faster or more reasonable timescales.

Another disadvantage of high resolution additive manufacturing is thatinternal stresses occur due to the slight shrinkage of the polymericmaterial during curing. When objects with overall dimensions exceedingabout 1 mm are fabricated by high resolution additive manufacturing,these internal stresses scale with size, and objects which are greaterthan 1 mm in size become unstable. Hence, there is a need to fabricateobjects such as razor blades using high resolution additivemanufacturing without internal stresses.

SUMMARY OF THE INVENTION

The present invention provides a simple, efficient method formanufacturing one or more cutting edge structures, such as razor bladesfrom a polymeric material and a functional polymeric cutting edgestructure such as a razor blade. Moreover, some methods are suitable forproducing a plurality of such cutting edge structures, or “blade boxes”comprising a plurality of razor blades formed in a polymeric material tobe disposed as a single unit in a razor cartridge.

The steps of the present invention process include providing a computermodel of a cutting edge structure, providing a liquid precursor materialdisposed within a container, immersing at least one substrate into theliquid precursor material, curing portions of the liquid precursormaterial in a focal point defined by a lens of an electromagneticradiation while the at least one substrate is disposed in the precursormaterial, wherein a wavelength of the radiation is about double awavelength required to cure the liquid precursor material, moving thefocal point of the radiation within the precursor material to form atleast one cutting edge structure on the substrate based on the model,and removing the substrate with the at least one cutting edge structurefrom the liquid precursor material in the container.

In one aspect, the substrate includes a blade body or blade support forthe at least one cutting edge structure. In another aspect, an extendedcutting edge is formed of closely spaced cutting edge elements.

The step of moving the focal point further includes movement of the lensin any direction, or movement of the container in any direction, or anycombination thereof. The at least one cutting edge structure is formedof a plurality of voxels. The precursor material is comprised of amonomer material, an oligomer material, or any combination thereof. Theat least one cutting edge structure may include a gothic arch, a romanarch, or one or more undercuts. A tip radius of the at least one cuttingedge structure is less than 1 micrometer. The precursor material iscomprised of an acrylic based material.

In another aspect, at least one of the precursor material or the curedpolymeric material is transparent to electro-magnetic radiation at awavelength in the range of 250 to 1500 nanometers.

The removing step further includes physical or chemical removal of thesubstrate from the cured polymeric material cutting edge structure.

A photo-initiator of about 1 to about 3% by weight of composition isadded to the second precursor material prior to the curing step. Thestep of curing includes cross-linking or polymerization.

In another embodiment, the at least one cutting edge structure is arazor blade or a portion of a blade box. The invention further includesthe step of assembling the razor blade or the blade box into a razorcartridge housing or frame.

In another aspect, the razor blade of the present invention includes acutting edge structure comprised of a polymeric material, the polymericmaterial produced on a substrate disposed in a liquid precursor materialfor the polymeric material, portions of the liquid precursor materialcured in a focal point defined by a lens of an electromagnetic radiationwherein a wavelength of the radiation is about double a wavelengthrequired to cure the liquid precursor material. In another aspect, atleast one of the precursor material or the cured polymeric material istransparent to electro-magnetic radiation at a wavelength in the rangeof 250 to 1500 nanometers. Further, the substrate comprises a blade bodyor blade support. Further still, the cutting edge structure comprises anextended cutting edge formed of closely spaced cutting edge elements.

In another embodiment, a blade box includes at least one cutting edgestructure, at least one non-cutting edge structure coupled to the atleast one cutting edge structure, and both the cutting and non-cuttingedge structures comprised of a polymeric material, the polymericmaterial produced by a liquid precursor material for the polymericmaterial wherein portions of the liquid precursor material are cured ina focal point defined by a lens of an electromagnetic radiation whereina wavelength of the radiation is about double a wavelength required tocure the liquid precursor material.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow diagram of a first method of manufacturing razor bladesfrom polymer, according to a preferred embodiment of the presentinvention.

FIG. 2 is a diagram of various example substrates capable of being usedfor the process of FIG. 1 according to the present invention.

FIG. 3 is a close-up micrograph view of the razor blade cutting edgeformed using the process of FIG. 1.

FIG. 4 is a top micrograph view of an array of cutting edge structuresof the present invention.

FIG. 5 is a diagram of an extended polymer cutting edge structure.

FIGS. 6A and 6B are a micrograph view of the extended cutting edge shownin FIG. 5 formed using the process of FIG. 1.

FIG. 7 is a front view of a razor cartridge having polymer razor bladesmade with the process of FIG. 2, according to one embodiment of thepresent invention.

FIG. 8 is a top view of a plurality of blade boxes in a base structure,each having a plurality of blades and a frame in another embodiment ofthe present invention.

FIG. 9 is a top view of an entire razor cartridge of the presentinvention.

FIG. 10 is a perspective view of a structure having a plurality ofnon-linear cutting edges formed therein according to a still furtherembodiment of the present invention.

FIG. 11 depicts various shapes of present invention cutting edgestructures.

DETAILED DESCRIPTION OF THE INVENTION

The methods of the present disclosure provide for the manufacture ofcutting edge structures (e.g., razor blades, which may be used inshaving devices or razors). Specifically, disclosed are methods formanufacturing cutting edges or razor blades for shaving devices frompolymeric material.

As used herein, a polymeric material signifies a material that is formedof a polymer, the latter being a large, chain-like molecule made up ofmonomers, which are small molecules. Generally, a polymer can benaturally occurring or synthetic. In the present invention, preferredembodiments comprise synthetic or semi-synthetic polymers. The syntheticor semi-synthetic polymer materials generally can occur in two forms orstates. The first state may be a soft or fluid state and the secondstate may be a hard or solid state. Generally synthetic polymers aremolded or extruded when in the first state (e.g., liquid or soft) andsubsequently formed into an object that is in a second state (e.g., hardor solid). In some instances, the material is reversible (e.g., amaterial in the second state can be converted back to its first state)while in others, the polymerization is irreversible (e.g., the materialcannot be converted back to its first state).

A thermoplastic polymer is a type of reversible polymer that is in asoft or liquid first state at elevated temperatures (e.g. 200° C. andabove) and converts to a solid second state when cooled to ambienttemperatures. Thermoplastic polymers are typically used for injectionmolding or extrusion techniques of the prior art.

For those polymeric materials where the second state is obtained fromthe first state via irreversible polymerization, the first state of thepolymeric material may generally be thought of as being a “precursor”for the second state of the polymeric material. As such, in the presentinvention, a polymeric material may be generated from a precursormaterial or a material in a first state.

The materials that are generally desired for the present inventioncutting edge structures are materials in the first, soft or liquid,states which comprise monomers or short chain length (e.g., lowmolecular weight) polymers known as oligomers or both. Both monomers andoligomers are referred to herein as “precursors.” These precursors areconverted into long chain length polymeric material in the second, solidstate through a polymerization or cross-linking process, herein referredto as a curing process. Curing the precursor material can generally beachieved under the influence of heat, light, ionic or high energyradiation, or any combination thereof. After curing, the solid polymericmaterial is achieved.

In FIG. 1, a flow diagram 20 of a method of manufacturing razor bladesfrom a polymeric material according to a preferred embodiment of thepresent invention is illustrated.

At step 50, a computer model of a 3-dimensional physical object isprovided. The 3-dimensional object of the present invention is desirablya razor blade though it may be a razor cartridge housing or othercomponents of the razor such as the guard, or the cap or lubricationelements, or any combination of components thereof.

At step 55, electromagnetic radiation from a source 56 can be focused bya lens system 58 into a focal point 60 with dimensions less than 10micro-meters, more preferably with dimensions down to about half of theradiation wavelength, (e.g., about 0.12 micro-meters to about 0.50micro-meters).

At step 105 a reservoir or container 115 is provided. The reservoir orcontainer may be of any type, shape or size but is preferably selectedto offer sufficient space in which to form cutting edge structures suchas razor blades.

A liquid precursor material 315 is preferably selected to fill thereservoir or container 115 as shown in step 205. There is generally nolimitation to the types of the precursor material that can be usedthough it is desirable that a fluid precursor material is used and thatthe material can be converted (e.g., cured) from the fluid state to asolid polymeric state by exposure to electro-magnetic radiation. In thisregard, the fluid has to be transparent for electromagnetic radiation.Desirably the filling or pouring step 205 of the present inventionoccurs at ambient temperature ranging from about 10 degrees Celsius toabout 40 degrees Celsius or may be heated up to 100 degrees Celsius toreduce its viscosity.

At step 305, a solid physical substrate 215 is immersed into the liquidprecursor material 315 in the reservoir 115. The substrate may have asmooth surface and may preferably be planar. The substrate may becomprised of glass, silicon, sapphire, diamond, ceramic steel or anotherpolymeric material in the present invention. Roughness values of thesubstrate ranging from about 100 nano-meters to about 1 nano-meter arecontemplated in the present invention.

The substrate 215, regardless of material composition, may have anyshape or profile feasible for forming cutting edges for razor blades. Itmay be a flat or extended substrate, on which entire razor blades arefabricated, or it may consist of a base merely for the edge such as ablade body or a blade support. Various types of substrates 215 that canbe used for the process of FIG. 1 are shown in FIG. 2. For example, aplanar or flat substrate, the type A shown, is contemplated in thepresent invention as is a blade body, the type B, or a blade supportsubstrate, the type C, also shown. Each of these substrates has asurface 216 onto which the polymeric cutting edge structure will beformed in step 405.

After the substrate 215 is immersed into the liquid precursor materialat step 305, the precursor material 315 in the liquid first state iscured such that it becomes a polymeric material in the second solidstate. This is accomplished at step 405 by directing the focal point 60of the electro-magnetic radiation into the liquid precursor material 315contained in the reservoir 115 to convert the transparent liquidprecursor material 315 into a solid polymeric material in the volumeelement (hereinafter referred to as “voxel”) 415 illuminated by thefocused radiation. The drawing at step 405 of FIG. 1 depicts theresultant voxel utilizing the 2PP process described below. Further atstep 405, the first voxel of the desired object will be produced in theliquid precursor 315 adjacent to the substrate 215, so that thecompleted object is anchored to the substrate surface 216.

For high resolution additive manufacturing, such as 2PP, theelectromagnetic radiation desirably has about double the wavelengthrequired to cure the precursor material (e.g., required to activate aphoto-initiator when used as described below), in order to cure thefluid polymeric precursor material. This wavelength generally rangesfrom about 250 nano-meters to about 1500 nano-meters, preferably between400 nano-meters and 1300 nano-meters. The source of electromagneticradiation 56 emits power sufficient to create a finite probability thattwo photons can be absorbed simultaneously by the fluid polymericprecursor material 315 in the focal point 60 to produce a solidpolymeric voxel 415. Desirably, the electromagnetic radiation is emittedin very short (e.g., femtosecond) pulses in order to reduce requiredaverage power of the source 56 to a feasible level (e.g., 100milli-Watts).

At step 505, the focal point 60 of the electromagnetic radiation can bedisposed over different voxels 415 to fabricate the object 510,preferably by moving or scanning focal point 60 within or through theliquid precursor 315 in the reservoir 115 by moving the lens 58 in anydirection, while keeping the source 56 centered on the lens 58. Arrows506, 507, 508 depict three possible directions of movement of the lens58 though the directions of movement may be angled or rotated in anymanner. Alternately, the reservoir 115 may be moved according to thecomputer model 50 in any direction. In addition, a combination of bothlens and reservoir movements in different directions may be utilized inthe present invention

To accelerate the fabrication of object 510 in step 505, multipleradiation sources 56 and/or lenses 58 (not shown) may be utilized inparallel to create multiple voxels 415 simultaneously.

In either scenario, a multitude of solid polymeric material voxels 415are produced that combined together represent the three-dimensionalphysical object 510 or objects desired (e.g., one or more razor blades)in step 515. The cutting edge structure 510 represents the structure inthe shape of a final cutting edge or razor blade edge.

After step 515 of FIG. 1, the solid polymeric structure 510 can beremoved from the reservoir. At step 605 in FIG. 1, the solid polymericstructure 510 that was formed, along with the substrate 215, aredesirably removed together from the reservoir 115. For instance, if thesubstrate 215 serves as a blade support for the edge structure 510 thismay be the last step prior to cleaning step 715 and assembly step 905 ofthe cutting edge structures in a hair removal device as indicated by thearrow 805. As shown at step 705 of FIG. 1, the solid polymeric structure510 can also be physically or chemically removed from the substrate(e.g., if the substrate is not a blade body of type B or a blade supportof type C or otherwise necessary), revealing a completedthree-dimensional object 510 for assembly in step 905. Acrylic basedsolid polymeric structures may be removed from the substrate using e.g.propylene glycol monomethyl ether acetate (PGMEA) andn-methyl-2-pyrrolidone (NMP) based solvents.

Prior to assembly step 905, as shown in step 715 of FIG. 1, it may benecessary or beneficial to remove or wash out any excess of uncuredmaterial or other remains from the surface or any cavities formed of thethree-dimensional solid polymeric object 510 (e.g., a fabricated cuttingedge structure or blade). Suitable wash agents or solvents include1-propanol or isopropanol.

Utilizing the process of the present invention, based on the 2-photonpolymerization process (2PP), which produces structures by scanning thefocal point of a high intensity electromagnetic radiation in 3dimensions within or through a bath of photo-curable precursor accordingto a CAD specification to fabricate an object 510 with sub-micrometersized features, a polymeric object 510 formed from sub-micrometer sizedvoxels with a tip radius 45 of about 250 nm has been demonstrated as canbe seen in FIG. 3 disposed on a substrate 42. The fabricated object 510is a cutting edge structure 40 which has a blade tip 44 and two facets46 and 48 that diverge from the tip 44. Thus, as shown in FIG. 3, thesolid polymeric structure 40 produced by the process of FIG. 1 has theshape and profile of a razor blade with desired tip radius (e.g., lessthan 1 μm).

An array 49 of solid polymeric cutting edge structures 40 can beproduced by the process of FIG. 1 as shown in the micrograph of FIG. 4which depicts a view from the top of the blade edge elements 40 arrangedin a 5×5 array 49 and residing on a glass substrate 42.

In the present invention, the polymeric material is preferably anacrylic based material, more preferably a polymer with monomer oroligomer formulations such as Femtobond 4B, supplied by Laser ZentrumHannover e.V., Germany, or E-SHELL® 300 supplied by EnvisionTEC GmbH,Germany, and most preferably polymeric materials from the ORMOCER®family, such as ORMOCORE, supplied by Microresist Technology GmbH.

A photo-initiator of about 1 to about 3% by weight of composition may beadded to the second polymeric material prior to the curing step 405 inFIG. 1. Photo-initiators generally start the polymerization orcross-linking (e.g., curing) process of the precursor of a polymericmaterial by absorbing radiation of a specific wavelength, commonlyvisible or UV light, and creating radicals that react with the monomersor oligomers and link them together. A photo-initiator commonly usedwith acrylate based precursors is alpha hydroxy ketone, sold under thetrade name of IRGACURE® 184 by BASF. In the case of ORMOCORE, aphoto-initiator may be IRGACURE® 369 also by BASF.

If a photo-initiator is used, the polymeric material is transparent at aspecific wavelength in this range, optimally chosen for the usedphoto-initiator. Hence, the precursor and the cured solid polymer of thepresent invention generally need to be at least partially transparentfor the wavelength of the electromagnetic radiation to be effective. Thetransparency selection of the polymer is necessary for effectiveness ascuring or polymerization of the whole object (e.g., cutting edgestructure) generally cannot occur when using light if the light cannotpenetrate below the surface of the polymer.

Alternatively, materials including any photo-curable polymer known in3D-printing, stereo-lithography, medical applications (e.g., dentistry)or bonding can be used as long as curing (e.g., polymerization orcross-linking or both of the monomeric or the oligomeric precursor) canbe achieved by exposing the precursor to electromagnetic radiation.Hence, desirably, the precursor and the cured polymer generally shall betransparent for the desired frequency of the electromagnetic radiation.

Shrinkage occurring during curing leads to internal stresses, whichbuild up over extended dimensions and may cause fracture of the extendedpolymer objects when in use. It has been demonstrated that thisdisadvantage can be overcome by producing a series of narrow (e.g., lessthan 1 mm wide) closely spaced cutting edge elements 218 adjacent toeach other that are joined to form an extended cutting edge structure219 with an extended cutting edge 220 as shown in FIG. 5. The separateclosely spaced cutting edge elements 218 and a portion of the extendedcutting edge structure 219 and extended edge 220 are visible in themicrograph of FIG. 6A. The micrograph in FIG. 6B shows the entireextended cutting edge structure 219 with lateral dimensions of about 1.2mm long, about 0.45 mm high and about 4 μm wide.

The dimensions of the cutting edge structures are in the range ofcentimeters. When fabricating the entire cutting structure solely by ahigh resolution additive manufacturing process such as 2PP, the overallblade size may be limited to millimeters length because to achievesub-micro meter resolution, the scanning steps have to be small which inturn requires a long time to fabricate large-scale (e.g., on the orderof centimeter) objects. Theoretically this can be overcome by firstcreating a larger blade body or blade support using conventional stereolithography (e.g., 1-photon polymerization) at low resolution and highscanning speed onto which the cutting edge is added at sub-micrometerresolution using the 2PP process. Alternatively, the fabrication processmay be accelerated by using a blade body of type B or a blade support oftype C, as shown in FIG. 2.

The tip radius of the cutting edge structure produced by the presentinvention process is desirably in the range of less than about 1micrometer. The hardness of a polymeric cutting edge structure formed,such as with ORMOCER®, may reach near 100 MPa after curing.

While a conventional razor blade wedge profile is similar to the typeshown in FIGS. 3 and 6A, the present invention contemplates cutting edgestructures with any number of facets, e.g., more than 2 or 3, and thesefacets need not be planar. Several exemplary shapes of the presentinvention are shown below in FIGS. 10 and 11 though any desirable,feasible shape is contemplated in the present invention.

It may or may not be necessary to remove the cutting edge structure fromthe substrate. In either case, each cutting edge structure that isproduced can be generally assembled individually into a razor cartridge.For example, if a cutting edge structure does not include a bladesupport type substrate, one or more polymer razor blades may be adheredto blade supports (e.g., with glue, ultrasonic welding) and assembledinto razor cartridge housings. Furthermore, the cutting edge structureblades can be processed or coated if necessary prior to assembly into arazor cartridge at step 905 of FIG. 1.

A razor cartridge 70 having one or more cutting edge structures or razorblades 72 made of polymer 74 of the present invention can be assembledas shown in FIG. 7. Razor cartridge 70 is similar to razor cartridgesthat are commercially available utilizing steel blades which are cuttingelements and with non-cutting edge structures such as the plasticelements housing and frame components 76. In assembly step 905, thepolymeric razor blades 72 can be secured to a mounting assembly prior tobeing inserted into the frame 76 or housing or they may be mounteddirectly on the frame.

While the methods of manufacturing described herein have been referredto with primary reference to a single cutting edge structure (e.g.,razor blade), the methods are easily applicable to the manufacture ofmultiple cutting edge structures simultaneously.

Turning to FIG. 8, a plurality of razor blades 82 may be formedclustered together in groups of three blades with a small frame 84. Theframe in FIG. 8 is a non-cutting edge structure while the razor bladesin FIG. 8 are cutting edge structures. The clusters have a generallyrectangular shape and for ease in discussion are referred to herein asblade boxes 86. The plurality of razor blades 82 can be manufactured inthis clustered organization to reduce downstream process steps in theshaving razor system assembly. The blade boxes 86 have 3 individualrazor blades 82, as illustrated, enclosed by a frame 84. The blade boxes86 can be manufactured identically or they can be different, such aseach box having differences in blade spacing, included blade angles,number of blades, orientation of the blades, and the like. Thedifferences can be made via changes to the computer model of the cuttingedge structures. A blade box 86 can be removed from the base structurein the same manner as described above, but such that the self-containedblade box 86 is a singular unitary part. In FIG. 9, a blade box 86 isinserted into an opening 92 in the housing 94 of a razor cartridge 90and secured therein or be formed into a razor cartridge entirely at theoutset (not shown).

Assembling the razor cartridge in such a manner eliminates the somewhattime consuming or difficult steps of affixing each individual razorblade to a blade support or to a housing, inserting each bladesupport-razor blade pair or each blade in the razor cartridge housing,and aligning each separate razor blade to the desired blade height,angle, and spacing. By utilizing the method described herein, theplurality of razor blades are aligned and secured in the blade box,thereby eliminating the need to affix individual blade supports and thedifficult process of aligning 3 or more separate razor blades into therazor cartridge housing. While FIG. 8 illustrates blade boxes 86 having3 razor blades, it is to be understood that any number of razor bladescan be clustered together, such as 2, 4, 5, or more.

While the blades illustrated in the figures thus far have generallylinear blade edges, other blade shapes and edge patterns can be producedby the methods described herein.

To that end, in a still further alternative embodiment, differentcutting structures in addition to straight edged or wedge-shapedconfiguration for blade edges are also contemplated in the presentinvention.

These other shapes are produced by using a process of FIG. 1 thatcomprises a different computer model of the 3-dimensional object. Insome instances, a sheet of material 151 may be the 3-dimensional objectwith openings 154 that contain internal cutting edges 152 that arenon-linear is produced by the process in FIG. 1 using a substrate frame153, as shown for instance in the blade box 150 of FIG. 10.

Any number of shapes or profiles for the cutting edge template, andhence, for the cutting edge structure or structures that will be formed,is contemplated in the present invention. The present inventionincludes, but is not limited to, the additional illustrative embodimentsdepicted in FIG. 11. Two arched cutting edge profiles, e.g., a gothicarch profile 162, a roman arch profile 164 are shown in FIG. 11 thoughany other feasible shape of the cutting edge structure is encompassed bythe present invention (e.g., wavy, serrations, saw teeth, etc.).Additionally, a cutting edge profile 166 having one or more undercuts167 is also shown in FIG. 11.

Accordingly, other embodiments are within the scope of the followingclaims.

Examples/Combinations

-   -   A. A method for manufacturing at least one cutting edge        structure comprising the steps of:        -   providing a computer model of a cutting edge structure;        -   providing a liquid precursor material disposed within a            container;        -   immersing at least one substrate into said liquid precursor            material;        -   curing portions of said liquid precursor material in a focal            point of an electromagnetic radiation while said at least            one substrate is disposed in said precursor material;        -   wherein a wavelength of said radiation is about double a            wavelength required to cure said liquid precursor material;        -   moving the focal point of said radiation within said            precursor material to form at least one cutting edge            structure on said substrate based on said model; and        -   removing said substrate with said at least one cutting edge            structure from said liquid precursor material in said            container.    -   B. The method of paragraph A, wherein the substrate comprises a        blade body or blade support for said at least one cutting edge        structure.    -   C. The method of paragraphs A or B, wherein an extended cutting        edge is formed of closely spaced cutting edge elements.    -   D. The method of paragraphs A, B, or C, wherein said moving the        focal point step further includes movement of said lens in any        direction, or movement of the container in any direction, or any        combination thereof.    -   E. The method of any of the preceding paragraphs, wherein said        at least one cutting edge structure is comprised of a plurality        of voxels.    -   F. The method of any of the preceding paragraphs, wherein said        precursor material is comprised of a monomer material, an        oligomer material, or any combination thereof.    -   G. The method of any of the preceding paragraphs, wherein said        at least one cutting edge structure comprises a gothic arch, a        roman arch, or one or more undercuts.    -   H. The method of any of the preceding paragraphs, wherein a tip        radius of said at least one cutting edge structure is less than        1 micrometer.    -   I. The method of any of the preceding paragraphs, wherein said        precursor material is comprised of an acrylic based material.    -   J. The method of any of the preceding paragraphs, wherein at        least one of said precursor material or said cured polymeric        material is transparent to electro-magnetic radiation at a        wavelength in the range of 250 to 1500 nanometers.    -   K. The method of any of the preceding paragraphs, wherein the        removing step further comprises physical or chemical removal of        the substrate from said cured polymeric material cutting edge        structure.    -   L. The method of any of the preceding paragraphs, wherein a        photo-initiator of about 1 to about 3% by weight of composition        is added to the second precursor material prior to the curing        step.    -   M. The method of any of the preceding paragraphs wherein said        step of curing comprises cross-linking or polymerization.    -   N. The method of any of the preceding paragraphs, wherein said        at least one cutting edge structure is a razor blade or a        portion of a blade box.    -   O. The method of paragraph N, further comprising the step of        assembling said razor blade or said blade box into a razor        cartridge housing or frame.    -   P. A cutting edge structure comprised of a polymeric material,        said polymeric material produced on a substrate disposed in a        liquid precursor material for said polymeric material, portions        of said liquid precursor material cured in a focal point of        electromagnetic radiation wherein a wavelength of said radiation        is about double a wavelength required to cure said liquid        precursor material.    -   Q. A cutting edge structure of paragraph P, whereby the        substrate comprises a blade body or blade support.    -   R. A cutting edge structure of paragraphs P or Q, wherein said        cutting edge structure comprises an extended cutting edge formed        of closely spaced cutting edge elements.    -   S. The cutting edge structure of paragraphs P, Q, or R, wherein        said precursor material is comprised of a monomer material, an        oligomer material, or any combination thereof.    -   T. The cutting edge structure of paragraphs P, Q, R, or S,        wherein said at least one cutting edge structure comprises a        gothic arch, a roman arch, or one or more undercuts.    -   U. The cutting edge structure of any of the preceding        paragraphs, wherein a tip radius of said at least one cutting        edge structure is less than 1 micrometer.    -   V. The cutting edge structure of any of the preceding        paragraphs, wherein at least one of said precursor material or        said cured polymeric material is transparent to electro-magnetic        radiation at a wavelength in the range of 250 to 1500        nanometers.    -   W. The cutting edge structure of any of the preceding paragraphs        wherein said precursor material is cured by cross-linking or        polymerization.    -   X. The cutting edge structure of any of the preceding paragraphs        is a razor blade.    -   Y. A blade box comprising:        -   at least one cutting edge structure;        -   at least one non-cutting edge structure coupled to said at            least one cutting edge structure, both said cutting and            non-cutting edge structures comprised of polymeric material,            said polymeric material produced on a substrate disposed in            a liquid precursor material for said polymeric material,            portions of said liquid precursor material cured in a focal            point of electromagnetic radiation wherein a wavelength of            said radiation is about double a wavelength required to cure            said liquid precursor material.    -   Z. The blade box of paragraph Y, wherein said precursor material        is comprised of an acrylic based material.    -   AA. The blade box of paragraphs Y or Z, wherein said        electromagnetic radiation cures said precursor material in a        plurality of voxels by moving a focal point in any direction.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A method for manufacturing at least one cuttingedge structure comprising the steps of: providing a computer model of acutting edge structure; providing a liquid precursor material disposedwithin a container; immersing at least one substrate into said liquidprecursor material; curing portions of said liquid precursor material ina focal point of an electromagnetic radiation while said at least onesubstrate is disposed in said precursor material; wherein a wavelengthof said radiation is about double a wavelength required to cure saidliquid precursor material; moving the focal point of said radiationwithin said precursor material to form at least one cutting edgestructure on said substrate based on said model; and removing saidsubstrate with said at least one cutting edge structure from said liquidprecursor material in said container.
 2. The method of claim 1, whereinthe substrate comprises a blade body or blade support for said at leastone cutting edge structure.
 3. The method of claim 1, wherein anextended cutting edge is formed of closely spaced cutting edge elements.4. The method of claim 1, wherein said moving the focal point stepfurther includes movement of said lens in any direction, or movement ofthe container in any direction, or any combination thereof.
 5. Themethod of claim 1, wherein said at least one cutting edge structure iscomprised of a plurality of voxels.
 6. The method of claim 1, whereinsaid precursor material is comprised of a monomer material, an oligomermaterial, or any combination thereof.
 7. The method of claim 1, whereinsaid at least one cutting edge structure comprises a gothic arch, aroman arch, or one or more undercuts.
 8. The method of claim 1, whereina tip radius of said at least one cutting edge structure is less than 1micrometer.
 9. The method of claim 1, wherein said precursor material iscomprised of an acrylic based material.
 10. The method of claim 1,wherein at least one of said precursor material or said cured polymericmaterial is transparent to electro-magnetic radiation at a wavelength inthe range of 250 to 1500 nanometers.
 11. The method of claim 1, whereinthe removing step further comprises physical or chemical removal of thesubstrate from said cured polymeric material cutting edge structure. 12.The method of claim 1, wherein a photo-initiator of about 1 to about 3%by weight of composition is added to the second precursor material priorto the curing step.
 13. The method of claim 1 wherein said step ofcuring comprises cross-linking or polymerization.
 14. The method ofclaim 1, wherein said at least one cutting edge structure is a razorblade or a portion of a blade box.
 15. The method of claim 14, furthercomprising the step of assembling said razor blade or said blade boxinto a razor cartridge housing or frame.
 16. A cutting edge structurecomprised of a polymeric material, said polymeric material produced on asubstrate disposed in a liquid precursor material for said polymericmaterial, portions of said liquid precursor material cured in a focalpoint of electromagnetic radiation wherein a wavelength of saidradiation is about double a wavelength required to cure said liquidprecursor material.
 17. A cutting edge structure of claim 16, wherebythe substrate comprises a blade body or blade support.
 18. A cuttingedge structure of claim 16, wherein said cutting edge structurecomprises an extended cutting edge formed of closely spaced cutting edgeelements.
 19. The cutting edge structure of claim 17, wherein saidprecursor material is comprised of a monomer material, an oligomermaterial, or any combination thereof.
 20. The cutting edge structure ofclaim 16, wherein said at least one cutting edge structure comprises agothic arch, a roman arch, or one or more undercuts.
 21. The cuttingedge structure of claim 16, wherein a tip radius of said at least onecutting edge structure is less than 1 micrometer.
 22. The cutting edgestructure of claim 16, wherein at least one of said precursor materialor said cured polymeric material is transparent to electro-magneticradiation at a wavelength in the range of 250 to 1500 nanometers. 23.The cutting edge structure of claim 16 wherein said precursor materialis cured by cross-linking or polymerization.
 24. The cutting edgestructure of claim 16 is a razor blade.
 25. A blade box comprising: atleast one cutting edge structure; at least one non-cutting edgestructure coupled to said at least one cutting edge structure, both saidcutting and non-cutting edge structures comprised of polymeric material,said polymeric material produced on a substrate disposed in a liquidprecursor material for said polymeric material, portions of said liquidprecursor material cured in a focal point of electromagnetic radiationwherein a wavelength of said radiation is about double a wavelengthrequired to cure said liquid precursor material.
 26. The blade box ofclaim 25, wherein said precursor material is comprised of an acrylicbased material.
 27. The blade box of claim 25, wherein saidelectromagnetic radiation cures said precursor material in a pluralityof voxels by moving a focal point in any direction.